Fuse containing electric plug



Oct. 7, 1947. E. E. HOSMER FUSE CONTAINING ELECTRIC PLUG Filed lay 28,1946 FIG. 2.

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w M a gar/4 2? $312 Patented Oct. 7, 1947 UNITED STATES PATENT OFFICEFUSE CONTAINING ELECTRIC PLUG Elbridge E. Boomer, Rldley Park, Pa.Application May 28, 1946, Serial No. 672,741

1 Claim. 1

My invention relates to electric plugs and more particularly to plugsspecially adapted to be attached to feed wires of electric appliancessuch as fans, refrigerators, washing machines and the like.

The object of my invention is to provide an electric plug which isadapted to protect the main house fuses against being blown out in caseof an overload, shortrcircuit or the like, occurring in the appliance towhich the plug is attached.

Another object of the invention is to provide a plug adapted to giveprotection to the electric appliance to the feed wire of which the plugis attached against damage from disturbances on the main electric line.

Other objects of my invention may appear in the following specificationdescribing my invention with reference to the accompanying drawingillustrating a preferred embodiment of my invention. It is however, tobe understood, that my invention is not to be limited or restricted tothe exact construction and combination of parts described in thespecification and shown in the drawing, but that such changes andmodifications can be made, which fall Within the claim appended hereto.

In the drawing,

Figure 1 is a side view of the plug according to my invention partlyshown in section, and

Figure 2 is an end view of Figure 1.

Referring now to the drawing in detail the plug according to myinvention has a body block I ll made of any suitable nonconductivematerial.

This body block is formed to have a rectangular cross-section and arectangular longitudinal section. It has a vertically extending slottherein through which one leg II of an angularly shaped contact memberI2 extends. The other leg I3 of said member is comparatively muchshorter than leg I I and rests on top of the body block II. It has ahole therein through which a machine screw I 4 extends. This screw I4engages the body block III threadedly and holds the contact member inposition.

The leg II of the angular member I2 extends beyond the lower surface ofthe body block III and forms one prong of the electric plug. The slot inthe body portion through which this leg extends is located adjacent oneof the end surfaces of the body block III.

A bore I5 extends through the body block IIl adiacent the other endsurface thereof. It has a counterbore on its surface end. On its lowerend it has a threaded counterbore which ends in a rectangulardepression.

(Cl. zoo-115.5)

A contact plate I6 rests on the top of the body block I0 and is fastenedthereon by a machine screw I 1. It extends over the bore IS in the bodyblock I0 and has a sleeve forming a socket I 8 thereon extendingdownwardly therefrom into the upper counterbore of the bore I5.

A fuse I9 of the cartridge type is located in the bore I5 and a helicalspring 20 is also located in the bore I5 and arranged underneath thefuse I 9.

A second angular contact member 2I has a short leg 22 located in therectangular depression in the under surface of the body block ID. Alonger leg 23 of the angular member 2I extends downwardly from the bodyblock III and forms the second prong of the electric plug.

A flat head screw 24 engages the thread of the lower counterbore of thebore I5 and the screw head is located in a circular depression in theshort leg 22 of the angular member 2I arranged coaxially with the boreI5 in the body block III, holding the member 2| in position.

The screw 24 engages the helical spring 20 urging this fuse into firmcontact with the sleeve I 8 on the contact plate I6. To replace the fuseI8 in case of necessity, the screw 24 is removed, so that the spring 20and the fuse I9 can be easily removed and replaced. A protector cap 25has a hollow upwardly extending body 26 having a downwardly extendingskirt 21 thereon, which surrounds the body block III. Countersunkmachine screws 28 secure the protector 25 in position on the body block.

A hole 29 is provided in the top of the hollow protector cap 25 and acable 30 extends through said hole. This is the feeding cable for anyappliance to be equipped with the plug according to my invention and isconnected with the prongs I I and 23 by being clamped underneath theheads of the screws I4 and I1.

The above description should make it clear that the use of a plugaccording to my invention in connection with any electrical appliancewill protect this appliance against damage by any overload on or defectin the main electric line and also should protect the main fuses againstblow outs in case of defects or overloads on the appliance, because theconnection between the appliance and the main line would be broken inany case of overload or defect on either side before any further damagecould occur either on the appliance or on the main line.

Having described by invention, I claim as new and desire to secure byLetters Patent:

In an electric plug, a body, a prong extending through said body, saidbody having a bore therethrough, a contact plate mounted On top oi saidbody and having a socket positioned in said bore, a second prong mountedonthe bottom of said body and having a, flange with a hole thereinregistering with the bore through the body, a, screw mounted in the holein said flange, a. cartridge fuse received at one end in said socket,and a compression spring positionedintermediate the other end of saidfuse and the screw.

ELBRIDGE E. HOSMER.

REFERENCES crrEn The following references are of record in the flle ofthis patent:

5 UNITED STATES PATENTS Number Name Date 1,657,799 Kellner Jan. 31, 19281,926,936 Casingena et a1. Sept. 12, 1933 10 2,232,679 Felke Feb. 25,1941

